排序方式: 共有25条查询结果,搜索用时 15 毫秒
1.
2.
3.
Pt/Ti Electrodes of PZT Thin Films Patterning by Novel Lift-Off Using ZnO as a Sacrificial Layer 下载免费PDF全文
We achieve a successful novel lift-off of patterning Pt/Ti electrodes on SiO2/Si substrates by employing ZnO sacrificial layer deposition and patterning, successive uniform Pt/Ti deposition and final lift-off. Then we deposit PZT thin films on the electrodes. Compared with the conventional lift-off processes for the electrodes, this novel process does not need post-annealing, which must be performed after conventional lift-off process. It is demonstrated that the electrodes patterned by the novel lift-off process have stronger adhesion. The electrodes and the PZT films on the electrodes are more compact and smoother than those by the conventional lift-off process. 相似文献
4.
5.
6.
Detection and Location of a Target in Layered Media by Snapshot Time Reversal and Reverse Time Migration Mixed Method 下载免费PDF全文
A target in layered medium can be located by the ridge-like distribution time reversal and reverse time migration(TR-RTM) mixed method. However, this method cannot distinguish between acoustic field distributions of the interface and target for the wider acoustic pulse signals, which may result in inaccurate location of the target. A snapshot TR-RTM mixed method is proposed to solve this problem. The principle of snapshot TR-RTM mixed method is first given. Experiments are then carried out, and a mountain-like acoustic field distribution is obtained by processing experimental data. The results show that the location of the peak is that of the target, and the ratio of the scattered signal and interface reflection signal(signal-to-interference ratio) is improved by about four times after processing. Furthermore, this method can effectively suppress the interface reflection signal and enhance the target scattering signal. Therefore, it can achieve effective detection and location of a target in a layered medium. 相似文献
7.
机械品质因数QM是高次谐波体声波谐振器(High-overtone Bulk Acoustic Resonator,HBAR)一个关键的特性参数。首次较系统地研究了QM随构成HBAR的3个组成部分(基底、压电薄膜和电极)的结构参数(厚度)和性能参数(特性阻抗与机械衰减因子)的变化规律。在谐振频率附近,将HBAR的分布参数等效电路简化为集总参数等效电路,首次用解析表达式给出它们的变化规律,分析了QM在给定频率最近谐振点的变化情况。结果表明,固定压电层厚度,QM随基底厚度的连续增加略呈振荡(非单调)上升,当基底厚度很大时趋于基底材料的机械品质因数;固定基底厚度,QM随压电层厚度的连续增加呈波浪式下降;选择低损耗的蓝宝石或YAG作为基底可以获得较大的QM值;电极的损耗必须考虑,它会降低QM值;与Au电极相比,具有较低损耗的A1电极选择适当厚度可以获得较高的QM值;此外,QM随频率的增加呈下降趋势。上述的结果为HBAR的优化设计提供了相应的理论依据。根据我们对Keff2的研究,QM与Keff2的变化规律往往是相悖的,因此在设计HBAR时要在这两者作适当的权衡。 相似文献
8.
9.
10.